This core is designed to support and advance our efforts to overcome the major shortcomings in risk adjustment and performance measurement needed to ensure that any health care reform (whether the currently legislated one or alternatives) results in improved efficiency. This Core is intended to provide key support for an ongoing initiative intended to advance the science of health risk, health outcome and health system performance measurement, while accelerating the broad scale adoption of more comprehensive, meaningful and reliable measures of health risk and health outcomes. First, the Core would support the development, testing and implementation of innovative measures of risk and outcome using Health and Retirement Survey (HRS), geographic based approaches and patient reported measures obtained from participating organizations. The core will assemble the databases needed to develop the measures described in Project 5 and will provide the infrastructure to support the collection and use of patient-reported measures by the three participating health systems. Second, it would support the Dartmouth Patient-Reported Measures Trust, which has two distinct but related goals: (a) to work with key stakeholders to build consensus on meaningful measures of health risks, health outcomes and health system performance, and (b) to help accelerate delivery system adoption and use of these measures. We anticipate that these collaborative efforts could yield key dividends in the next several years - patient-reported health measures (and biomarkers) across a wide range of health systems for use in Subprojects 1, 2, and 4. Finally, the Core would disseminate to collaborating investigators the advanced measures developed through this work. The Core will be able to provide to other investigators participating in this P01 (and through Core A, others in the research community where permissible) the following critical measures: (a) innovative measures for risk adjustment for use in all P01-related analyses using the Medicare data and HRS data; (b) innovative measures of risk and performance at the system level, beginning with the 3 pilot sites and (we hope) expanding to additional sites.